draft-ietf-6man-rfc4291bis prohibiting non-/64 subnets

[Nick Hilliard <[e-mail]>]

as it's currently worded, draft-ietf-6man-rfc4291bis seems to prohibit
the implementation of any interface netmask != /64:

>                                           However, the Interface ID of
>    all unicast addresses, except those that start with the binary value
>    000, is required to be 64 bits long.

This has substantial operational consequences in the ipv6 world because
if it's implemented as stated, it will cause production ipv6 networks to
break.

The ipv6 operational community may have opinions on the wisdom of
mandating new behaviour which would cause their networks to fall over,
so it would probably be a good idea to notify v6ops@ietf about the
existence of this draft so that the folks over there get a look-in
before a consensus call is made. As far as I can tell, this notification
never happened.

Nick